The author and green-living expert reveals his favorite eco-friendly products

Author and green-living expert Seo has campaigned for environmental issues since he was 12 and recently launched the bath and body line Wholearth. "I emphasize lifestyle as much as sustainability," he says.

TOP TIP: "Store paraben-free products in a cool place," he says. "They'll last longer." Wholearth uses kimchi enzymes as a preservative.

GREEN SCREEN: Beware misleading numbers. "If a product says it's 80 percent natural, check the other 20 percent." Also, "Some companies have their own certification programs, which is like being your own American Idol judge. Look for the USDA or Ecocert seals," he says.